Electron discharge device of the cavity resonator type



Dec. 360, 1947. a R. P. STONE 2,43%34 ELECTRON DISCHARGE DEVICE OF THE CAVITY RESONATOR TYPE Filed July 29, 1944 INVENTORQ fimmn 5mm:

Patented Dec. 30, 1947 CAVITY RESONATOR TYPE Robert P. Stone, Grlggstown, N. J., assignor to Radio Corporation of America,

of Delaware a corporation Application July 29, 1944, Serial No. 547,189

SfClaims, (01. 315- My invention relates to electron discharge devices useful at ultra high frequencies andmore particularly to such devices utilizing cavity resonators.

In such devices, particularly those used as oscillators at ultra high frequencies and employing input and output resonators, it is necessary to provide suflicient feedback energy from the output resonator to the input resonator to over- In this arrangement the indirectly heated cathode I0 is supported on cathode block I l and anode I2 is supported on anode block [3. The elongated grid plates l4 and I5 support the grid wires l'6 therebetween. Insulating spacer members l0" and I3 are utilized to insulate the electrodes from each other and to permit different direct voltages to be applied to the various electrodes. This elongated unit structure is enclosed within an outer envelope of conducting material in which the electrode assembly and cavity resonator circuits are mounted. This envelope comprises the elongated 'U-shaped elements l1 and I8 sealed at the lip I8. The insulating spacers l1 and ll" thus necessitating additional elements. If the I resonators form part of the tube elements, extra seals for the lines are necessary. Furthermore, in devices of this kind sparking occurs in those parts of the system which are not placed within vacuum.

It is therefore an object of my inventionto provide an electron discharge device employing cavity resonators of improved design and useful as "oscillators.

A further object, of my invention is to privide such a device having feedback means which does not require outside coaxial lines which must be tuned.

More specifically it is an object of my invention to provide feedback by simple capacity means within the device.

A further object of my invention is to provide such a device in which the feedback means are operated within a vacuum, thus reducing or sub- -stantially eliminating sparking.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims, but the invention itself will best be understood by reference to the following descriptiontaken in connection with the accompanying driwing in which Figure l is a section transverse to the longitudinal axis of an electron discharge device and associated circuit employing my invention, and- Figure 2 is a section taken along the line IIII of Figure 1.

In Figures 1 and 2 is shown an electron discharge device and associated circuit and utilizing my invention. The electron discharge device and circuit are described and claimed in a copending application of Russell R. Law, Serial No. 542,717, filed June 29, 1944, and assigned to the same assignee as the present application.

insulate the anode and cathode and the resonators from the envelope. The grid is grounded on the envelope by elements [4 and [5. The space enclosed between cathode and grid forms the input resonator and between grid and anode, the output resonator.

The leads for the cathode comprisev tubular members 20 and 2| sealed through appropriate apertures in the envelope and are provided with insulating cup shells 25 and 26 secured to tubular extensions 23 and 24. Either may be used as cathode lead and one of the cathode heater leads, the other side of the cathode heater being connected to the lead 35 sealed through an aperture in the envelope by means of the cup-shaped element 31. The tubular leads 20 and 2| communicate with the passage 22 through the cathode block and may be used for cooling purposes.

The tubular anode leads 2! and 28 are likewise sealed through appropriate apertures in the envelope of the tube, being hermetically sealed therein by means of insulating cup-shaped members 3| and 32 sealed to the collar elements 29 and 30, the bellows portion, such as 33 being provided on the collar members to provide for expansion and contraction of the various elements during operation of the device. These members 21 and 28 communicate with passageway 34 in the anode block. A cooling medium may be circulated through these members and passageway.

Output loop 4| terminating in a hermetically sealed coaxial line permits extraction of high frequency energy from'the grid-anode space or output cavity resonator, which is separated from the grid-cathode space or input cavity resonator by means of the partition elements 39 and 40.

In accordance with my invention I provide a I feedback between the output and input resonators entirely within the evacuated envelope and without the use of coaxial feed lines. I mount on the cathode block II a pair of elongated rectangularshaped conducting elements 23 and 24 which extend past the grid and into recesses provided in the ends of the anode block. The ends of the conducting members 43 and 44 however are out of contact with the anode block and are merely capacity coupled to the anode block. This is sufficient to provide a coupling between the input and output resonators to feed energy from the output resonator between the grid and anode to the input resonator between the grid and cathode. The conducting elements could be mounted on either electrode. Because the elements are mounted with a vacuum, difliculties due to sparking are substantially eliminate While. I have indicated thepreferred embodiments of my invention of which I am now aware and have also indicated only one specific application for which my invention may be employed, it will be apparent that my invention is by no means limited to the exact forms illustrated or the use indicated, but that many variations may be made in the particular structure used and the purpose for which it is employed without departing from the scope of my invention as set forth in the appended claims.

I claim:

1. An electron discharge device including adjacent elongated like capacity resonators having a common wall provided with an elongated aperture. a grid electrode mounted in said aperture, an anode insulatingly supported by the wall of one of said cavity resonators and extending toward said grid and a cathode insulatingly supported by the resonator wall of the other cavity resonator and extending toward said grid from the opposite direction for supplying a stream of electrons along a predetermined path to said anode, said cathode and anode being in registering positions on opposite sides of said grid, and being coextensive with the longitudinal walls of said resonator, and an elongated conducting member supported at one end of said cathode and extending past said grid, and overlying the end of said anode but out of contact therewith for feeding energy from one resonator to the other for maintaining oscillations, said elongated conducting member lying outside of the direct path between said cathode and said anode, said anode having a recess for receiving the end of said conducting member.

2. An electron discharge device for use at ultra high frequencies and employing like cavity resonators, and having an elongated cathode electrode along a predetermined path-after anode electrode" insert-in the path of said electrons for receiving said electrons, an elongated anode electrode and grid therebetween, said electrodes and said grid being mounted within an evacuated envelope, means for capacity coupling said electrodes and including an elongated conducting member supported at the end of one of said electrodes and extending past said grid and overlapping the other of said electrodes but out 0!- contact therewith for providing feedback for sustaining oscillations, said other electrode having a recess into which said conducting member extends, said conducting member lying outside of the direct path of electrons from said cathode to said anode. 7

3. An electron discharge device for use at high frequencies and having an elongated cathode electrode for supplying electrons along a predetermined path, an elongated anode electrode in the path of said electrons for receiving said electrons and a grid therebetween, and a cavity resonator coupled between said cathode electrode and said grid, and a like cavity resonator coupled between said grid and anode electrode, and an elongated conducting member supported at each end of said cathode electrode and extending past said grid and overlying the ends of the anode electrode but out of contract therewith for capacity coupling said cathode and anode electrodes for providing feedback. for sustaining oscillations, said conducting members lying outside of the direct electron path between said cathode and said anode, said anode having a recess at each end thereof for receiving the ends of said conducting members.

ROBERT P. STONE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,157,952 Dallenbach May 9, 1939 2,287,845 Varian et al. June 30, 1942 2,128,236 Dallenbach Aug. 30, 1938 Patent N5, 2,433,634.

numbered patent requiring correction as follows:

Certificate of Correction December 30,1947. ROBERT P. STONE It is hereby certified that errors appear in the grilnted speiificaggmfof the abgv e oumnl, 'e or-prlvie read provide; line 43, for driwing read drawing; column 4, lines 4 and 5, claim 2,-

strike out after anode electrode insertand insert instead the comma and words an elongated anode electrode; lines 6 and 7, same claim, strike out an elongated anode electrode"; and that the same Letters Patent should be read with these &rections therein that the same may conform to the reeord of the case in the Patent.

Signed and sealed this 4th day tr May, A. D. 1948.

moms F. MURPHY, I WQWDIPM. 

